Rates Of Reaction (Textbook)

Question 1

What were the vast majority of material in our world made by?

Answer 1

Chemical reactions

Question 2

Give an example of a fast and slow reaction

Answer 2

• Explosions are fast reactions
• Rusting is a slower reaction

Question 3

What are the variables which affect the rate of a chemical reaction?

Answer 3

• Temperature
• Concentration (of reactant)
• Particle size/ surface area
• Use of a catalyst

Question 4

How can rates of reaction be increased?

Answer 4

• increasing the temperature
• increasing the concentration of a reactant
• increasing surface area/ decreasing particle size
• through the use of a catalyst

Question 5

What must happen for a chemical reaction to take place?

Answer 5

For any chemical reaction to take place the reacting particles must collide with enough energy in order to combine and form new products.

Question 6

What is the effect of increasing the temperature on the rate of a chemical reaction and why does this happen?

Answer 6

Increasing the temperature increases the rate of reaction because the particles collide with more energy

Question 7

What is the relationship between temperature and the rate of reaction?

Answer 7

• the higher the temperature, the faster the reaction.
• the lower the temperature, the slower the reaction.

Question 8

When can concentration be changed?

Answer 8

Concentration can only be changed for reactions that are in solution.

Question 9

What is the effect of concentration on a chemical reaction and why?

Answer 9

If the concentration of the reactants in increased, there are more reactant particles moving moving around in the same space. There will be more collisions and so the reaction rate is increased.

Question 10

What is the relationship between concentration and the rate of reaction?

Answer 10

• The higher the concentration, the faster the reaction.
• The lower the concentration, the slower the reaction.

Question 11

When can particle size be changed?

Answer 11

Particle size can only be changed for solid reactions

Question 12

What is the effect of surface area on the rate of reaction and why?

Answer 12

The greater the surface area area, the higher the chance of collisions occurring and thus the faster the rate of reaction.

Question 13

What is the relationship between particle size and the rate of reaction?

Answer 13

• The smaller the particle size, the faster the reaction.
• The larger the particle size, the slower the reaction.

Question 14

What is the benefit of using catalysts?

Answer 14

Catalysts allow reactions to be carried out at lower temperatures, saving both energy and money.

Question 15

What is an enzyme and when can it be used?

Answer 15

Enzymes are biological catalysts. Enzymes can be used in industrial processes such as the fermenting of sugars to produce alcohol.

Question 16

What is a catalyst?

Answer 16

Catalysts are substances that speed up chemical reactions but can be recovered chemically unchanged at the end of the reaction.